Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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OCN: 247L YORKSTREAM COMMUNICATIONS LLC

NPA-NXX BLOCK Rate Centre Region Switch LATA LIR Eff date Disc date
406-455 A Great Falls MT   648      
406-455 7 Great Falls MT   648   2025-10-06   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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